<!doctype html>

<html>
<head>
    <title>web client</title>
</head>

<body>
    <h1>DateString[]</h1>
    <div id='result'></div>
    <script>
const request = new XMLHttpRequest();
const url = 'http://127.0.0.1:5858';
data = 'DateString[]';
request.onload = function() {
    document.getElementById("result").innerHTML = request.responseText;
}
request.open('POST', url, true);
request.send(data);
    </script>

</body>

</html>